why download them if you allready have them? Yes, there is a way to get at them. You need a DAT tool like DatManLite or (the one i use) DAT Explorer, then exract the sounds you want (of which will be in .acm file format, fallout's sound format) and use a utility like acm2wav or acmconv to convert the sounds to .wav files.
You will notice that the sounds you play will appear to be a bit faster... it's coz they are. Fallout's sounds are played at 50% speed because it saves space. If your familar with images and the concept of interlacing (removing every second line in an image.. eg: starcraft 1's movies) then it's ideally the same thing, but for sound.
the next obvious step is do do something cool like replace them with your own sounds which is easy enough. Just get a cool gun sound to replace whichever sound file you want, go into the generic Windows Sound Recorder, change the format, reduce speed by 50%, use a tool like snd2acm to convert it back to an acm, then put that sound file under the original sound's name into the directory which it belongs in (typically something like Fallout 2/Data/Sound/sfx.. depending on where you got the sound from) and try it out in the game.